1. Field of the Invention
The presented techniques are related to a resin composition and a method of stably forming a fine pattern in a semiconductor process by using the resin composition as a coating layer of a photoresist.
2. Description of the Related Art
Development is accelerated by a trend of high quality and a high integration of semiconductor devices, and by development of the lithography processes. According to above trend and development, a chemically amplified photoresist corresponding to a miniature of deign rule is also developed. However, in general, minimum resolution realized by using an ArF exposure apparatus is about 0.05 μm. Therefore, it is difficult to manufacture a high integrated semiconductor devices that need fine patterns, and then variable methods are considered to overcome above problems.
As an example method that is widely used by this time includes a resist thermal reflow method allowing a liquidity to a photoresist by heat-treating to the photoresist. By this method, a size of a contact hole may be reduced by heat-treating the photoresist at a temperature over a glass transition temperature of the photoresist after the contact hole is formed on the photoresist. However, by this method, a top-rounding and a undercut are generated, so that a control of critical dimension may be difficult.
Another method that used to overcome the above method may include using a functional materials such as RELACS (manufactured by CLARIRANT Co., Switzerland) and SAFIER (manufactured by TOKYO OHKA KOGYO CO., LTD., Japan) to reduce a size of the pattern. The method using a functional materials lead to a cross linkage between the functional materials and the photoresist an interface in that the size of the contact hole may be reduced. However, the method using the functional materials needs to repeat cross linkage process at least a several times to decrease an efficiency. Also, the functional materials are poor at an anti-etching characteristic because they don't have a bulky portion in the polymer. Furthermore, the method above is insufficient to meet a coating characteristic required to the pattern, and it is difficult to control a thickness of the cross-linkage under the heat-treating process.